This invention relates to methods and systems for allowing a programmable controller to communicate with a remote computer.
Programmable controllers operate elaborate industrial equipment, such as robots, in accordance with a plurality of stored control programs. When executed, each program causes the controller to examine the state of the controlled machinery by evaluating signals from one or more sensing devices (e.g., position encoders, temperature sensors, or pressure sensors) and to operate the machinery (e.g., by controlling the output voltage for servo motors, or energizing/de-energizing discrete components) based on a procedural framework, the sensor signals and, if necessary, more complex processing.
The programmable controller is generally described as a computer-based control unit that is represented by an aggregate of conventional elements, including a central processing unit, a crystal controlled clock, random access memory, communication channels, digital and analog input/output ports and D/A and A/D converter channels. The control unit also supports a user interface, which may include a teach pendant and/or video display terminal, to facilitate operator input of processing programs, commanded positions, and system parameters.
One known method and system to overcome this problem is disclosed in U.S. Pat. No. 5,805,442 to Crater et al, entitled xe2x80x9cDistributed Interface Architecture For Programmable Industrial Control Systems.xe2x80x9d Crater et al. shifts the burden of providing user interfaces for changing forms of data from the remote computer to the controllers. This is accomplished by combining data with functionality for displaying that data at the individual controllers. Each of the controllers has a computer memory for storing the relevant data and formatting instructions, i.e., web pages, associated with the data that allow a properly equipped remote computer to display the data in a predetermined format. Thus, each type of data has a web page associated with it stored in the controller""s memory. However, this adds complexity and increased memory capacity to the programmable controller.
Thus, there exists a need for enhancing communication between a programmable controller and a remote computer while still allowing the remote computer to access different types of data.
It is an object of the present invention to provide an efficient and simple method for enabling communication between a programmable controller and a remote computer having varying types of data objects stored therein.
In carrying out the above object, a method for allowing a programmable controller to communicate with a remote computer is provided. The method includes receiving a request from the remote computer for one of the data objects stored in the programmable controller, determining the type of the data object being requested and automatically converting the data into a comprehensible format based on the type of the data object, generating a user display in response to the request for transmission to the remote computer, and utilizing the user display at the remote computer to allow a user to access the comprehensible format of the requested data.
Still further, in carrying out the above object, a system is provided for performing the steps associated with the method of the present invention. The system includes an interface module at the controller for receiving a request from the remote computer for one of the data objects stored in the programmable controller and a data converter module for determining the type of the data object being requested and automatically converting the data into a comprehensible format based on the type of the data object. The interface module generates the user display in response to the request for transmission to the remote computer. The remote computer includes a display for displaying the user display to allow a user to access the comprehensible format of the requested data.
These and other features of the present invention can be understood from the following specification and drawings.